In recent years, the spread of personal computers has been remarkable. In a personal computer, a pair of electric connectors used for the board-to-board connection, and a pair of electric connectors used for the wire-to-board connection are provided.
For example, an electric connector fixed to an outer surface of a power board which controls a power source and an electric connector fixed to a mother board on which a CPU is mounted are connected together. One electric connector is a plug type connector having a connecting projection, while the other electric connector is a receptacle type connector having a connecting recess.
Conventionally, as a receptacle type electric connector of this kind (as disclosed in, for example, JP-A-11-067364), an electric connector having terminal retainer recesses opened in the connector-joining direction and formed in each of a pair of side walls which define a connecting recess has heretofore been provided.
With demands for the miniaturization and a higher function of a personal computer body, the electric connector of this kind has also demanded the miniaturization thereof and an increase in the number of electrodes thereof.
In general, the depth of the terminal retainer recesses between the electric connectors of this kind is set to 12 to 13 mm. In the meantime, it is demanded that the width of each of the terminal retainer recesses be set to, for example, around 0.4 mm, and that the intervals (pitch) at which the terminal retainer recesses are arranged be set to, for example, around 0.6 mm. In this electric connector, it is necessary that the thickness of each partition wall between adjacent terminal retainer recesses be set to, for example, as extremely small as 0.1 mm.
Therefore, in order to meet these demands in the connector disclosed in the above-mentioned JP-A-11-067364, the following new problems arise.
In a metal mold for molding a housing, it is necessary that terminal retaining recess-molding ribs be made thin (for example, 0.4 mm), and that the intervals of the ribs be set small (for example, 0.6 mm). However, when the terminal retainer recess-forming ribs are thus formed, there is a fear of deforming the ribs due to the pressure occurring during an injection molding operation. When the ribs are deformed during an injection molding operation, the thin partition walls (having a thickness of, for example, 0.1 mm) between the terminal retainer recesses are also deformed. In addition, the position accuracy of the terminal retainer recesses is deteriorated, and in its turn the position accuracy of the terminals decreases. As a result, the reliability of the electrical connection of the connectors lowers.